1910 Very Rev. Mother Marie Louise De Meester, Foundress of the ICM Congregation and three Sisters arrived in Tagudin, Ilocos Sur, Philippines.
1911 Rev. Fr. Devesse, CICM built a little chapel which also served as a classroom for 10 children on Cathedral Hill where ICM Sisters helped manage the class.
1913 Three ICM Sisters formally established Holy Family Academy at Campo Filipino with 57 children (Primary Grades).
1915 A Trade School was started which offered silversmithing for boys and lace making for the girls.
1916 The elementary course (Grades 1 through 7) was completed. The Trade School was expanded; silversmithing, lace making, woodcarving, carpentry, tailoring and shoe making were included in the curriculum for industrial arts.
1916 The elementary course (Grades 1 through 7) was completed. The Trade School was expanded; silversmithing, lace making, woodcarving, carpentry, tailoring and shoe making were included in the curriculum for industrial arts.
1921 The high school department for girls only was started in Holy Family Academy.
1929 Saint Louis School, Inc. (Center), Assumption Road, had its first high school graduation.
1945-46 After World War II, the ONLY co-ed group of high school graduation was held at Saint Louis School, Campo Filipino.
1946-51 Separate departments for boys and girls in the high school at Saint Louis School, Inc., Assumption Road resumed with the ICM Sisters.
1951 Saint Louis School, Inc., maintained the High School department exclusively for girls. The boys went to St. Louis College, Baguio (now SLU) to start their Laboratory High School exclusively for boys with the CICM fathers.
1991 After the Earthquake of 1990, the two ICM schools, Saint Louis School Campo Filipino and Saint Louis School Center merged into: SAINT LOUIS SCHOOL, INC. Elementary Department at Assumption Road and Girls’ High School Department at Quirino Highway (Naguilian Road)
2005 The School began co-education program in the High School Department
2010 The School participated in the celebration of the ICM Philippine District Centennial.
2011 The School celebrated its 100 Years Centennial Graced History of existence!
2013 The high school department passed the First Formal PAASCU ACCREDITATION and topped the ESC Re-certification in the Cordillera Administrative Region (CAR).
2016 The high school department has started the implementation of the Senior High School Program offering the Academic Track with the strands: Science, Technology, Engineering and Mathematics (STEM), Accountancy and Business Management (ABM), & Humanities and Social Sciences (HUMSS).
2017 The high school department was granted LEVEL II REACCREDITED STATUS by The Federation of Accrediting Agencies of the Philippines (FAAP) for having satisfactorily met the standards and fulfilled all the requirements of the Philippine Accrediting Association of Schools, Colleges and Universities (PAASCU). 2018 The high school department held its first grade 12 graduation.
2016-2018 For three (3) years in a row, the high school department was recognized by the Department of Education as BEST PERFORMING SECONDARY SCHOOL (Private School Level) in the Division of Baguio and in the Cordillera Administrative Region (C.A.R.)
2020 SLSI shifted to new normal realities in education due to the COVID-19 pandemic.
